A win or victory of some nature which falls in the following categories
-An overwhelming Victory over an opponent
-A victory thats been snatched from the jaws of defeat
-An unexpected victory from an underdog
-Something fantastic thats happened or worked out unexpectably well

Guy 1:How the hell did you do that!?
Guy 2:It was a good win yes
Guy 1:No, it was more than that, it was an Epic Win!